A12 Back leak

[bat]

Hi

When I develop a roll out of my A-12 back the photo area is perfect but the very edges of the negative have some black areas. They appear to have been exposed. Is this a sign of a light leak in the back or is it likely that I am making some other error, possibly in the removal of the film from the back. Thanks for your help.

 

[hasselbladtech]

This is most likely due to a worn light trap. This part prevents light from entering the film magazine when the dark slide is removed.

David S. Odess - Factory trained Hasselblad technician

 

[tckline]

If black is at the edge of the film, not at edges where frames are adjacent, then the light leaked to the film when the roll was out of the camera. Light can penetrate along the film edge next to the spool of 120/220 film. This is one reason why one is cautioned not to espose rolls to direct sunlight.
BTW it is quite an effort to reply to a query on this forum!
Regards
Tom in Alaska

 

[tckline]

PS., If the light leak is due to a bad trap, the leakage is asysmetric, being on the side of the film that was next to the dark slide slot.

 

[bat]

Thanks for your advice Tom and David, I will do some testing.

 

[janikphoto]

ummm, if it was a LIGHT leak, wouldn't it show up as a WHITE area and not a black area as described above?!? anyway, i had a roll or two with some white and i think i may need to replace the seals. I'm waiting for my extra film to come back just to make sure. I took it to a different lab incase the first lab was the prob... anyway, anyone know which side of the neg would have the light marks, i think it would be the left side when viewing a print or slide from the affected film...

 

[ruben]

Jason As Tom says the leak is in the side were you insert the dark slide - light on a sllide -black on a neg. The is a guy in california that sell them pretty cheap - they are not original but the work rather well - and afte replace the first to you get the hang of it and stop loosing al the small screws and parts

 

[qnu]

The leak will be on the side where you insert the slide, but more often than not the effect of it is on the other side (notched edge) of the film.
The slide opening is not at the same level as the film, meaning the light has to reach the film at an angle. So it will strike the film closer to the opposite edge, the "near side" being shielded by the wall separating film and opening levels.
That's why the blotches will appear near the notched edge.